Forging brass alloy containing small amounts of beryllium



United States Patent "Office 3,1504% Patented Jan. 19, 1965 -3,166,410 FURGINGBRASSALLOY CGNTAI'NKNGSMALL 'AMOUNTS F BERYLLIUM Philip S. Hanson, Mfyomissing, and Robertll. Saxtan,

Reading, Pa, assignors' to The Beryliiunr Corporation, Reading, Pa., a corporation of Delaware No Drawing. Filed Apr. 29, 1963, Ser. No. 276,155

,5 Claims. (ill. 75-453) This invention relates generally to improvements in forging brass alloys. g

A general object of the present invention is to provide a new forging brass alloy composition which can be hot forged, easily machined-and 'hardencd and in which the machining may 'bedone in the hardened state.

Standard "brass -forgings --are -so-ft after forging, hav- "ing 'Rockwellreadings in- "the neighborhood- --of- 575-80.

Such standard forging brass having aRockwell hardness of F-78 is not subject to thermal treatments for changes in hardness except to a very minor degree. Such standard forging brass is generally measured on'the Rockwell F scale. Rockwell B readings are generally below Rockwell B50.

The objectives of the present invention to improve the properties of forging brass are attained by the addition 58.0-68.0 percent copper 1.5-2.5 percent lead .18-.7 percent beryllium "B ala'nce-Zinc The solution-heatt-reating temperature for this'im- .18 to .7 percent is extremely fine grained, easily workable and capable of being hardened by solution heat treating, quenching and ageing.

The solution heat treating temperature for this improved alloy is in the range of from 1050 F. to 1500 F. The higher temperatures for the solution heat treating increase the percentage beta present and thus higher or greater hardness is obtained after ageing. V The preferred ageing temperature for the alloy is 600 F. for a period of approximately 3 hours. Temperatures lower than 600 F. may be used for a longer period of time and temperatures above 600 F. will accelerate the ageing and therefore a shorter time can be used.

The preferred composition has a beryllium content within the range of from .25 to .4 percent.

A percentage lower than .18 percent of beryllium in the alloy will bring about a slight increase in hardness due to solid solution hardening but the response to ageing treatments is somewhat less than that obtained when the beryllium content is above .18 percent and within the range set forth above.

The following tabulations set forth the different properties for the alloy having the beryllium content within the stated nominal composition range and as distinguished between solution annealed and quenched material and materials subject to solution annealing, quenching and ageing, employing the solution heat treating temperatures in the range hereinabove set forth and the ageing temperature stated.

In the alloy composition having a beryllium content higher beta percentages in the area of .2 percent, a Rockwell B hardness increase of from 3 to 5 points will be shown between the solution annealed and quenched materials and solution anneal, quench, and age as follows:

.2% Be typical properties:

Solution anneal-Rockwell B-60-68 Solution anneal and ageRockwell B68-72 Where theberyllium content of the alloy is on the high side as, for example, approximately .6 percent in the composition, a considerable increase in solid solution hardening plus age hardening response is shown in accordance with the following set forth properties:

6% Be typical properties:

Solution anneal-Rockwell B70-80 Solution anneal and ageRockwell B92-100 The Rockwell range is a function of the solution annealtemperature. The low range represents lower temperatures which display greater ductility. The

lower beta percentages and higher Rockwell readings mean and less ductility.

For the preferred beryllium range in the composition, namely, the mid range values of from .25 to .4 percent beryllium, the typical properties are as'follows: Solution anneal-Rockwell B60-80 Solution anneal and age-Rockwell B82-95 Anneal 1275 F. and quench-Rockwell B60-70 Age 600 F. for 3 hours-Rockwell B85-90 Anneal at 1275 F. and air coolRockwell B5060 Age 600 F for 3 hours-Rockwell B70-80 A specific example of the forging brass alloy of the present invention is given as follows:

Percent Copper 63.07 Lead 2.5 Beryllium" .50 Balance Zinc The foregoing alloy composition was annealed at 1250 F. for 30 minutes and water quenched. This sampsile stgf the alloy showed the Rockwell B hardness of Ageing the sample having the above composition for gshgurs at 600 F. showed a Rockwell B hardness of Samples of the beryllium brass were prepared and thermally treated and tested for mechanical properties.

The following table sets forth the chemical composition of three such samples having the identification markings set forth:

Identification Cu, Be, Pb, Zn

Percent Percent Percent Strip A 68 0.5 0. 5 Ba]. Rod 13---- 68 0. 5 0. 5 Bal. Rod O 63 0.5 2. 5 Bal.

Mechanical properties are as follows:

Table l-Beryllium brass strip i r 31.8., Total Elong, Rock- 0 Processing U.T.S., 0.2%, Strain Perwell p.s.i. p.s.i. under cent 13 Load, p.s.i.

1. Cold rolled from 2 .1880 t0..10#0 i 2 A 106,000 88,300 65,400 3 96 ame as 1 p us 3 lISDlIHIS Ft 11-? A- 98,300 84, 800 64, 300 10 96 1 our a 4 1%50" F., g.(l% 3 A 08, 600 29, 300 31, 500 43 65 ame as p us 5 lisoigsqat F.t 85, 500 55,800 49, 200 30 86 1%50' F., in 1000%. A 68,600 33,800 34, 500 37 08 6. amc as 5 p us hours at 600 F A 75, 400 43, 400 43, 400 30 78 Table II-Beryllium brass rod 0.5% Y.S., Total Elong., Rock- Proeessing U.T.S., 0.2%, Strain Perwell p.s.i. p.s.i. under cent B Load,

1131;. Cold (drawnt mm 1.0 ta. 0 .780 Elia 13-- 105,100 86,100 57,100 6 93 2. Same as #lB plus B 111,500 102,900 75,500 7 99 2 hrs at 60 O 96, 700 86,700 56,500 8 95 3. SILT. 3; hr at }B- 70, 600 35, 900 35, 900 38 69 1250 F., VV.Q. C 80, 400 41, 000 25, 500 20 81 4. Same as #3 plus 3 }B 93, 400 65, 900 64, 900 26 88 hrs. at 000 F. 0.- 100, 500 67, 000 47, 100 13 00 5. S.H.T. 2 hr. at }B 71,200 37,200 37,200 70 1250 F., Air Cool. 0-- 68,600 28, 500 17, 500 28 74 6. Same as #5 plus 3 }B 77,800 46, 000 46, 000 29 76 hrs. at 600 F. 0-. 79, 100 42, 300 34,400 23 78 35 V beryllium alloyed therein.

' We claim:

1. A forging brass alloy consisting of the following constituents in the following range proportion:

Percent Copper 58.0 to 68. 0 Lead 1.5 to 2.5 Beryllium 0.18 to 0.70 Balance Zinc 2. A forging brass alloy consisting of:

Percent Copper 63.07 Lead 2.5 Beryllium .50 Balance Zinc 3. A forging brass consisting of:

Percent Copper 63.07 Lead 2.5 Beryllium .50 Balance Zinc and having a Rockwell hardness of B-96.

4. A forging brass alloy consisting of 58 percent to 68 percent copper, 1.5 percent to 2.5 percent load, 0.18 percent to 0.70 percent beryllium, and the balance zinc,

- having a high beta content, a Rockwell B hardness of -97, and being fine grain.

5. A forging brass consisting of:

Percent Copper 58.0 to 68.0 Lead 1.5 to 2.5 Beryllium 0.18 to 0.70 Balance Zinc and having fine grain, high beta content, and capable of being hardened by solution heat treating, quenching and aging.

References Cited in the file of this patent UNITED STATES PATENTS 1,880,223 Weymouth et a1. Oct. 4, 1932 2,296,706 Corson Sept. 22, 1942 2,311,750 Hensel et a1. Feb. 23, 1943 

1. A FORGING BRASS ALLOY CONSISTING OF THE FOLLOWING CONSTITUENTS IN THE FOLLOWING RANGE PROPORTION: 